The proposed research attempts to evaluate the efficacy of the inclusion of activity schedules in the treatment of depressed individuals and isolate critical components in the procedure. The experiment compares the effects of self-monitoring, use of contingencies to increase activity level, and the use of specific (mood-correlated) activities, on depression level. Five groups of depressed subjects will be studied pre- and post-treatment and 30 days after the termination of treatment. Post hoc analyses of the data will be done with respect to the following questions: (1) Is an increase in pleasant activity level associated with a decrease in clinical depression level? (2) Are the subjective enjoyability ratings of depressed individuals when they are not in a depressed state different from those obtained from them when they are depressed? Previous research has shown the subjective enjoyability ratings of depressed individuals when they are in a depressed state to be lower than those obtained with normals and non-depressed psychiatric controls, a finding which is consistent with the "loss of reinforcer" hypothesis for depressed persons. (3) Are there systematic differences on the criterion variables between depressives differentiated on the endogenous-reactive continuum? BIBLIOGRAPHIC REFERENCES: Lewinsohn, P. M. Activity schedules in treatment of depression. In Krumboltz, J. D. & Thoresen, C. E. (Eds.) Counseling Methods. Holt, Rinehart, & Winston, 1976, pp 74-83. Lewinsohn, P.M. The behavioral study of depression. In Hersen, M., Eisler, R.M., & Miller, P.M. (Eds.) Progress in Behavior Modification. Academic Press, l975, pp. 19-64.